ANDES JSON

Overview

JSON is a portable format for storing data. It has been used in several other power system tools, including PowerModels, Pandapower, NREL-SIIP, and GridCal. It must be noted that JSON files from these tools are not interoperable because JSON only defines the data structure, not the meaning of data.

Compared with the xlsx file which is a zipped package, the ANDES JSON file is much faster to parse. We recommend that you use JSON in the following scenarios:

• Your test case is stable and require no manual editing, or

• You will read/write a large number of cases

To convert kundur_full.xlsx to the ANDES JSON format, do

andes run kundur_full.xlsx -c json

The output file will be named kundur_full.json.

Data storage

The ANDES JSON format uses one large dictionary for all devices in the system. The keys of the dictionary are the model names, and the values are lists of dictionaries. In each dictionary, the keys are the parameter names and the values are the parameter values.

The following shows the structure of a JSON file:

{
"Toggle": [
    {
    "idx": 1,
    "u": 1.0,
    "name": "Toggle_1",
    "model": "Line",
    "dev": "Line_8",
    "t": 2.0
    }  //      <- Toggle_1 ends
],     //      <- Toggle model ends
"Bus": [
    {
    "idx": 1,
    "u": 1.0,
    "name": 1,
    "Vn": 20.0,
    "vmax": 1.1,
    "vmin": 0.9,
    ...  //    <- other parameters are omitted
    },
    {
    "idx": 2,
    "u": 1.0,
    "name": 2,
    "Vn": 20.0,
    "vmax": 1.1,
    "vmin": 0.9,
    ...  //    <- other parameters are omitted
    },
    ...  //    <- other buses

],   //        <- Bus model ends
...  //        <- other models
}    //        <- whole system ends

There are thirdparty tools for editing JSON files, but we still recommend to convert files to xlsx for editing. The conversion can be readily done with

andes run kundur_full.json -c xlsx